"A benzene ring is a molecular structure that is created when six carbon atoms connect with each other in a linked ring. Each carbon atom has four electrons; two electrons link up with neighboring carbon atoms, while one goes to a hydrogen atom. The fourth is what is known as a delocalized electron, meaning that it is not directly involved with a specific atom. Benzene rings are often drawn as hexagonal shapes with a circle in the middle to represent these delocalized electrons. Benzene happens to be a particularly toxic form of aromatic hydrocarbon."